Transmission for piston and crankshaft assemblies



July 5, 1938. BOURKE 2,122,676

TRANSMISSION FOR PISTON AND CRANKSHAFT wASSEMBLIES Filed May 12, 1936 3 Sheets-Sheet 1 INVENTOR,

BYWJM ATTORNEYL' 3 Shets-Sheet 2 INVENTORT ATTORNEY.

R. L. BOURKE Filed May 12', 1936 TRANSMISSION FOR PISTON AND CRANKSHAFT ASSEMBLIES July 5, 1938.

July 5, 1938. BQURKE 2,122,676

TRANSMISSION FOR PISTON AND CRANKSHAFT ASSEMBLIES Filed ma 12, 1935 s Sheets-Sheet s lllll'llmlll INVENTORT' Boa/a6;

ATTORNEY.

Patented July 5, 1938 UNITED STATES PATENT OFFICE TRANSMISSION FOR PISTON AND CRANK- SHAFT ASSEMBLIES 4 Claims.

This invention relates to improvements in internal combustion engines and particularly to transmissions for crank shafts and pistons.

An object of my invention is to provide an improved engine having novel transmission means operatively connecting the pistons with the crank shaft.

Other and further objects of my invention will be pointed out hereinafter, indicated in the appended claims, orobvious to one skilled in the art upon an understanding of the present disclosure.

For the purposes of this application, I have elected to show herein certain forms and details of transmissions for crank shafts and pistons for internal combustion engines which are representative of my invention; the constructions herein shown and described, while capable of use with engines of various kinds, are particularly well adapted for use with internal combustion engines of the type disclose-d in my co-pending application for Letters Patent, Serial No. 726,321, filed May 18, 1934; it is understood, however, that the particular construction herein illustrated is not to be regarded as exhaustive of the variations of my invention nor is it to be given any interpretation such as might have the effect of limiting the claims, short of the true and most comprehensive scope of the invention in the art.

In the accompanying drawings:

Figure 1 is a vertical sectional view taken on the line I-| of Figure 2, showing a crankshaft and bearing assembly embodying my invention; and

Figure 2 is a sectional view taken on the line 2-2 of Figure 1.

Figure 3 is a vertical sectional view of a part of a crank case, showing a modified transmission assembly of the kind employed with a two cylinder engine; and

Figure 4 is a sectional View taken on the line 44 of Figure 3.

Referring to the drawings, the numeral l designates a crank case having centrally disposed bearings at its front and rear sides within which a crank shaft 2. is rotatably mounted. The crank case is provided with suitable inlet means for the insertion of lubricating oil, the normal level of which is slightly beneath the central axis of the said case, and with packing glands of the customary kind, which serve to prevent the escape of oil through the crank shaft bearings. The bearing at the front of the crank case through which the shaft 2 extends is particularly designed to eliminate any whip action on the end of said shaft and to take up the thrust ordinarily accompanying the fast rotation of said shaft in either direction. The shaft 2 is encircled by a thrust bearing 3 which is partly imbedded in an annular groove in the front side of the casing. Also, encircling the shaft 2 and spaced from the bearing 3 by a washer 4 and a flanged split bushing 5 which is partly imbedded in an annular groove in said shaft, is a similar bearing 6. A fiber or felt pad I encircling the shaft 2 is held against the front side of the bearing 6 by a front or nose plate 8 which is bolted to the crank case i and is so shaped and positioned that it encases the bearings 3 and 6 and maintains them in proper operating positions. The bearing 6 being in engagement with the split bushing 5 secured in a fixed position on the shaft. 2, the said bushing being in contact with the thrust bearing 3, and the latter being in engagement with the front side of the casing I, affords a novel and improved construction for taking up the thrust action. of the shaft, thereby preventing the usual damaging effect to the shafts crank arm or throw when the engine is operating at high speeds.

The rear end of the crank case is enclosed by a rear cover plate 9 having an inwardly disposed annular flange 9a within which a bearing I is mounted. The bearing ID is mounted on the hub of a circular gear I I to which is keyed the rear end of the shaft 2. A circular gear l2 having a rearwardly projecting rod I3 secured thereto for use in starting the engine, is in mesh with the gear II.

The crank shaft 2 is formed with a suitable crank arm or offset 2', which is adapted to dip into the oil in the crank case during its rotation, the said crank arm having a suitable split bushing l4 extending therearound. Mounted on the bushing "I4 is a bearing member l having an encircling ring l6 secured thereto. The bearing member i5 is mounted between two cooperating bearing plates I! and I8, each of which is formed in the shape of a circular disc. The bearing plates I 1 and [8 are provided respectively with .15 elongated slots l1 and I8 through which the crank arm 2' of the crank shaft rotatably and movably extends, the said slots being disposed at right angles to one another. Suitably secured as by bolts to the opposing faces of bearing plates 5 I l and I8 respectively, are blocks Ila and l8a which respectively provide opposing shoulders I lb and I 8?) over which the ring-shaped member l6 of the bearing l5 moves back and forth. The slots I1 and i8 are parallel to the shoulders Nb and I8!) respectively, thereby permitting the crank arm 2 and the bearing member l5 with its outer ring IE to move simultaneously back and forth. Formed integrally with, or otherwise suitably secured to the blocks Na and lBa are a number of connecting rods l9l which extend into oppositely disposed cylinders 20 bolted to the crank case I. The connecting rods 20 each slidably extends through a guide member 2! and is secured at its outwardly disposed end to a piston which is mounted for reciprocating motion in a cylinder 2! The crankshaft 2 and its crank arm 2' are provided with a continuous bore or breather channel 2a which is open to the atmosphere at a point outside the crank case and which provides means for permitting air or gases to proceed to and from the crank case I when the temperature of the engine changes. The inwardly disposed end of the channel 2a terminates at the rear end of the horizontal part of the crank arm 2 and at a point not in alignment with that part of the channel located in the shaft proper, thereby preventing theescape of the oilfrom the interior of the crank case, irrespective of what position the engine might assume.

As illustrated on the drawings, each of the bearings'S, 6, l and I is preferably made up of inner and outer circular spaced races between which are a number of steel balls. 7

In the modified form illustrated in Fi 4, wherein my improved transmission used in'anengine having-but two op inders and pistons, I have shown tw bearing plates 22 and 23 secured together by bolts 24. Interposed between the bearing plates, and suitably secured theretoas by bolts 24, are oppositely disposed blocks 25 which are formed integrally with or otherwise suitably secured to connecting rods I9 that extend into oppositely disposed cylinders attached to the crank case I. The bearing plates 22 and 23 are provided with centrally disposed elongated and aligned slots 26 which are positioned in a plane parallel to opposed parallel surfaces 250. provided on the blocks 25. Movably extending through the slots 26 is the crank arm 2' of a crank shaft 2, which has a split bushing l4 mounted thereon. Mounted on the bushing 14 is a bearing member l5 having an encircling ring secured thereto. The bearing member I5 is mounted between the spaced bearing plates 22 and 23 with its periphery movably engaging with the opposed. parallel surfaces 25a of the block 25. The parallel arrangement of the slots 26 of the cam plates with the surfaces 25a of the blocks 225 permits the crank arm 2 and the bearing member l5 to move back and forth in unison. The two concomprising a bearing member encircling the crank shaft, a pair of spaced bearing plates positioned on opposite sides of the bearing member, each having a centrally disposed elongated slot through which the crank shaft movably extends, the slots being positioned in planes positioned at right angles to each other, a pair of spaced blocks secured to the inner face of each bearing plate, each pair of said blocks having opposed surfaces lying in parallel planes, the said parallel surfaces of each pair of blocks being positioned in planes parallel to the longitudinal axis of the slot in the particular bearing plate to which its said blocks are secured, the said surfaces of the blocks being in engagement with the periphery of the bearing member, and connecting rods converging substantially toward a common center connecting the pistons to the blocks.

2. In an engine, transmission means connecting a plurality of opposed pairs of'pistons to a crank shaft, comprising a single circular bearing member secured on the crank shaft, 21. pair of slotted and spaced plates positioned at opposite sides of the bearing member through which the crank shaft movably extends, and a connecting rod secured to each piston having a block secured to its inwardly disposed end, the two blocks associated with each pair of opposed pistons being secured to the inner face of one of the plates near opposite ends thereof, the said blocks having inwardlydisposed surfaces with which the periphery of the bearing member engages.

3. In an engine, transmission means connecting a pair of opposed pistons to a crank shaft, cd'i j-prising a pair of spaced bearing plates having centrally disposed elongated and parallel slots through which the crank shaft movably extends, a pair of spaced blocks secured to and positioned between the bearing plates at opposite sides of the slots, the said blocks having opposed surfaces lying in parallel planes which are also parallel to the longitudinal axes of the slots in the bearing plates, connecting rods connecting the blocks and the pistons, a split bushing extending around the shaft, and a bearing mem-. ber encircling the bushing and positioned between the bearing plates with its periphery in engagement with the opposed surfaces of the blocks.

4. In an engine, transmission means connecting a pair of opposed pistons to a crank shaft, comprising a circular bearing member mounted on the shaft, a pair of spaced bearing plates positioned at opposite sides of the bearing member having centrally disposed elongated and parallel slots through whichthe crank shaft movably extends, a pair of spaced blocks secured to and positioned between the bearing plates at opposite sides of their slots, the said blocks having opposed parallel surfaces lying in planes parallel to the central longitudinal axis of the slots, the bearing member being positioned between the blocks with its periphery engaging with their parallel surfaces, and connecting rods connecting the blocks and the pistons.

RUSSELL L. BOURKE. 

